92 research outputs found
Adjoint BFKL at finite coupling: a short-cut from the collinear limit
In the high energy Regge limit, the six gluons scattering amplitude is
controlled by the adjoint BFKL eigenvalue and impact factor. In this paper we
determine these two building blocks at any value of the 't Hooft coupling in
planar =4 SYM theory. This is achieved by means of analytic
continuations from the collinear limit, where similar all loops expressions
were recently established. We check our predictions against all available data
at weak and strong coupling.Comment: 30 pages plus appendices, 12 figures. References added; published
versio
Experimental Infection of the Biomphalaria glabrata Vector Snail by Schistosoma mansoni Parasites Drives Snail Microbiota Dysbiosis.
Host-parasite interaction can result in a strong alteration of the host-associated microbiota. This dysbiosis can affect the fitness of the host; can modify pathogen interaction and the outcome of diseases. Biomphalaria glabrata is the snail intermediate host of the trematode Schistosoma mansoni, the agent of human schistosomiasis, causing hundreds of thousands of deaths every year. Here, we present the first study of the snail bacterial microbiota in response to Schistosoma infection. We examined the interplay between B. glabrata, S. mansoni and host microbiota. Snails were infected and the microbiota composition was analysed by 16S rDNA amplicon sequencing approach. We demonstrated that the microbial composition of water did not affect the microbiota composition. Then, we characterised the Biomphalaria bacterial microbiota at the individual scale in both naive and infected snails. Sympatric and allopatric strains of parasites were used for infections and re-infections to analyse the modification or dysbiosis of snail microbiota in different host-parasite co-evolutionary contexts. Concomitantly, using RNAseq, we investigated the link between bacterial microbiota dysbiosis and snail anti-microbial peptide immune response. This work paves the way for a better understanding of snail/schistosome interaction and should have critical consequences in terms of snail control strategies for fighting schistosomiasis disease in the field
Relationship between positive end-expiratory pressure levels, central venous pressure, systemic inflammation and acute renal failure in critically ill ventilated COVID-19 patients: a monocenter retrospective study in France
Background The role of positive pressure ventilation, central venous pressure (CVP) and inflammation on the occurrence of acute kidney injury (AKI) have been poorly described in mechanically ventilated patient secondary to coronavirus disease 2019 (COVID-19). Methods This was a monocenter retrospective cohort study of consecutive ventilated COVID-19 patients admitted in a French surgical intensive care unit between March 2020 and July 2020. Worsening renal function (WRF) was defined as development of a new AKI or a persistent AKI during the 5 days after mechanical ventilation initiation. We studied the association between WRF and ventilatory parameters including positive end-expiratory pressure (PEEP), CVP, and leukocytes count. Results Fifty-seven patients were included, 12 (21%) presented WRF. Daily PEEP, 5 days mean PEEP and daily CVP values were not associated with occurrence of WRF. 5 days mean CVP was higher in the WRF group compared to patients without WRF (median [IQR], 12 mm Hg [11-13] vs. 10 mm Hg [9â12]; P=0.03). Multivariate models with adjustment on leukocytes and Simplified Acute Physiology Score (SAPS) II confirmed the association between CVP value and risk of WRF (odd ratio, 1.97; 95% confidence interval, 1.12â4.33). Leukocytes count was also associated with occurrence of WRF in the WRF group (14 G/L [11â18]) and the no-WRF group (9 G/L [8â11]) (P=0.002). Conclusions In mechanically ventilated COVID-19 patients, PEEP levels did not appear to influence occurrence of WRF. High CVP levels and leukocytes count are associated with risk of WRF
Indicateurs de suivi de l'activité scientifique de l'Inria
La Commission d'Evaluation de l'Inria a mis en place début 2020, à la demande de la Direction Générale, un groupe de travail visant à réfléchir à des indicateurs pour l'analyse qualitative de l'activité scientifique de l'Institut. Ce document est le fruit des discussions de ce groupe, enrichies par les échanges avec la Direction Générale d'Inria et avec l'ensemble de la Commision d'Evaluation. Au-delà de cette « commande », il nous a semblé important de saisir cette opportunité pour mener une réflexion collective, qui dépasse le cadre de notre Institut, sur les indicateurs, et sur ce qu'ils peuvent ou ne peuvent pas dire de nos pratiques scientifiques
Knock Down of Heat Shock Protein 27 (HspB1) Induces Degradation of Several Putative Client Proteins
Hsp27 belongs to the heat shock protein family and displays chaperone properties in stress conditions by holding unfolded polypeptides, hence avoiding their inclination to aggregate. Hsp27 is often referenced as an anti-cancer therapeutic target, but apart from its well-described ability to interfere with different stresses and apoptotic processes, its role in non-stressed conditions is still not well defined. In the present study we report that three polypeptides (histone deacetylase HDAC6, transcription factor STAT2 and procaspase-3) were degraded in human cancerous cells displaying genetically decreased levels of Hsp27. In addition, these proteins interacted with Hsp27 complexes of different native size. Altogether, these findings suggest that HDAC6, STAT2 and procaspase-3 are client proteins of Hsp27. Hence, in non stressed cancerous cells, the structural organization of Hsp27 appears to be a key parameter in the regulation by this chaperone of the level of specific polypeptides through client-chaperone type of interactions
Environment and firewood use at Tourasse cave (south-west France) around the Late Glacial-Holocene transition
International audienc
Covariation between microeukaryotes and bacteria associated with Planorbidae snails
International audienceBackground: Microbial communities associated with macroorganisms might affect host physiology and homeostasis. Bacteria are well studied in this context, but the diversity of microeukaryotes, as well as covariations with bacterial communities, remains almost unknown.Methods: To study microeukaryotic communities associated with Planorbidae snails, we developed a blocking primer to reduce amplification of host DNA during metabarcoding analyses. Analyses of alpha and beta diversities were computed to describe microeukaryotes and bacteria using metabarcoding of 18S and 16S rRNA genes, respectively.Results: Only three phyla (Amoebozoa, Opisthokonta and Alveolata) were dominant for microeukaryotes. Bacteria were more diverse with five dominant phyla (Proteobacteria, Bacteroidetes, Tenericutes, Planctomycetes and Actinobacteria). The composition of microeukaryotes and bacteria were correlated for the Biomphalaria glabrata species, but not for Planorbarius metidjensis. Network analysis highlighted clusters of covarying taxa. Among them, several links might reflect top-down control of bacterial populations by microeukaryotes, but also possible competition between microeukaryotes having opposite distributions (Lobosa and Ichthyosporea). The role of these taxa remains unknown, but we believe that the blocking primer developed herein offers new possibilities to study the hidden diversity of microeukaryotes within snail microbiota, and to shed light on their underestimated interactions with bacteria and hosts
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